Fax issue and g711Ulaw64k

[David Coelho]

The error may not be on the router but I have to check. A remote office has implemented a new fax server and it routes through their voice gateway (I set up) through 2 ISDN lines.

They have issues with particular calls though.

The fax tech wrote:

calls rejected are showing a g711Ulaw64k protocol request we are rejecting
verify in configtool only able to configure g711 and ulaw alaw, no option for ulaw64k - g711 is a 64k protocol, however this appears to be odd as calls that are completed are showing g.711u and not the g711Ulaw64k. Advise to check with Cisco router admin first to see if they see the difference in data transfer protocols when their own logging is reviewed, and if so is the g711ulaw64k thing coming from an additional protocol option on the router, or is this coming back as response from Integra?

G711ulaw is enabled on the router. It does not seem like a random occurance but rather certain phone calls (yeah...I know). I just want to make sure I am not missing something on my end.

Thanks!

[Jonathan Schulenberg]

Well, there is only ulaw and alaw so that's likely a log oddity on their side.

What is the protocol between the fax server and the gateway?

Is it direct or through CUCM?

What do the traces look like for a suspect call?

What is the fax/modem relay/passthrough/pass-through configuration?

Please remember to rate helpful responses and identify helpful or correct answers.

[David Coelho]

Thanks for the reply! Since the errors are coming only from certain lines, I would hazard the error is elsewhere but I have to eliminate my peice.

What is the protocol between the fax server and the gateway?

h323

Is it direct or through CUCM?

Direct to the fax server. Does not go through CM

What do the traces look like for a suspect call?

What is the fax/modem relay/passthrough/pass-through configuration?

fax protocol t38 version 0 ls-redundancy 0 hs-redundancy 0 fallback none

fax send transmitting-subscriber $s$

[jbroderick]

G711ulaw is a 64k codec. What is the environment?

Sent from Cisco Technical Support iPad App

[chrysostomos1980]

Can you describe the call flow?

PRI?BRI?---VG-Right Fax via h323?

What actual is the problem? outgoing , incoming?

All the extensions into the Right Fax experiencing the same issue?or?

Please rate all useful posts 

Regards
Chrysostomos

""The Most Successful People Are Those Who Are Good At Plan B""

[David Coelho]

Two PRI comming into a voice gateway (plenty of DSP) then from the GW to the fax server via H323.

These are only used for outgoing calls. The errors seem destination specific to certain numbers.

Thanks you!

[chrysostomos1980]

David

Just to understand.The incoming faxes are ok only the outgoing have issues?

And the issue is to some specific destination numbers?

Please rate all useful posts 

Regards
Chrysostomos

""The Most Successful People Are Those Who Are Good At Plan B""

[David Coelho]

Well....no way to tell on incoming. This fax server is used 100% for outgoing faxes.

And it does appear this is only happens to certain number (which did work on the previous fax server solution but not with the new one and the new PRIs)

[chrysostomos1980]

can you collect a debugs into the VG?

Can you share your dial peer configuration for the fax server?

Pls be informed that at least you have to have configure one voip dial peer for the calls coming from the right fax

Example:

This dial peer is used for calls going to Fax server and also is used for incoming calls from the right fax

!

dial-peer voice 6 voip

description Dial-Peer to Fax Server

preference 1

destination-pattern 50..

session target ipv4:172.x.x.x (right fax ip)

incoming called-number ....

dtmf-relay h245-signal

codec g711alaw

fax-relay ecm disable

fax rate 14400

fax protocol t38 ls-redundancy 0 hs-redundancy 0 fallback cisco

no vad

Please rate all useful posts 

Regards
Chrysostomos

""The Most Successful People Are Those Who Are Good At Plan B""

[David Coelho]

Not sure what debug would be helpful here. There is a 1% failure in faxes so it would be hard to pinpoint unless there is a specific debug on errors.

dial-peer configs (sucked the numbers were not consecutive on the PRIs)

dial-peer voice 61 voip

destination-pattern 0202

session target ipv4:10.9.81.22

incoming called-number .

voice-class codec 1

voice-class h323 1

dtmf-relay h245-alphanumeric

fax-relay ecm disable

fax protocol t38 version 0 ls-redundancy 0 hs-redundancy 0 fallback none

ip qos dscp cs3 signaling

no vad

!

dial-peer voice 62 voip

destination-pattern 0210

session target ipv4:10.9.81.22

incoming called-number .

voice-class codec 1

voice-class h323 1

dtmf-relay h245-alphanumeric

fax-relay ecm disable

fax protocol t38 version 0 ls-redundancy 0 hs-redundancy 0 fallback none

ip qos dscp cs3 signaling

no vad

!

dial-peer voice 63 voip

destination-pattern 024[48]

session target ipv4:10.9.81.22

incoming called-number .

voice-class codec 1

voice-class h323 1

dtmf-relay h245-alphanumeric

fax-relay ecm disable

fax protocol t38 version 0 ls-redundancy 0 hs-redundancy 0 fallback none

ip qos dscp cs3 signaling

no vad

!

dial-peer voice 64 voip

destination-pattern 0269

session target ipv4:10.9.81.22

incoming called-number .

voice-class codec 1

voice-class h323 1

dtmf-relay h245-alphanumeric

fax-relay ecm disable

fax protocol t38 version 0 ls-redundancy 0 hs-redundancy 0 fallback none

ip qos dscp cs3 signaling

no vad

!

dial-peer voice 65 voip

destination-pattern 040[78]

session target ipv4:10.9.81.22

incoming called-number .

voice-class codec 1

voice-class h323 1

dtmf-relay h245-alphanumeric

fax-relay ecm disable

fax protocol t38 version 0 ls-redundancy 0 hs-redundancy 0 fallback none

ip qos dscp cs3 signaling

no vad

!

dial-peer voice 66 voip

destination-pattern 0293

session target ipv4:10.9.81.22

incoming called-number .

voice-class codec 1

voice-class h323 1

dtmf-relay h245-alphanumeric

fax-relay ecm disable

fax protocol t38 version 0 ls-redundancy 0 hs-redundancy 0 fallback none

ip qos dscp cs3 signaling

no vad

!

dial-peer voice 67 voip

destination-pattern 0396

session target ipv4:10.9.81.22

incoming called-number .

voice-class codec 1

voice-class h323 1

dtmf-relay h245-alphanumeric

fax-relay ecm disable

fax protocol t38 version 0 ls-redundancy 0 hs-redundancy 0 fallback none

ip qos dscp cs3 signaling

no vad

!

dial-peer voice 68 voip

destination-pattern 0418

session target ipv4:10.9.81.22

incoming called-number .

voice-class codec 1

voice-class h323 1

dtmf-relay h245-alphanumeric

fax-relay ecm disable

fax protocol t38 version 0 ls-redundancy 0 hs-redundancy 0 fallback none

ip qos dscp cs3 signaling

no vad

[Mahmoud.Reda]

Hi,

I am having the same problem. Does anyone find a solution to this issue.

Thank you

Best Regards

[gearbox]

David,

Thats a tough issue :D have you grabbed any packet captures on the gateway or fax server and listen to the fax call?  You can hear if there is any packet loss of timing issues between the CNG tones.  Also have you tried enabling T38 with fallback to G711ulaw?  Are the new PRIs from a new carrier?